Applicators for dispensing thermoplastic liquids, such as hot melt adhesives, typically operate at highly elevated temperatures, such as above about 250° F. Various dispenser or applicator configurations have high temperature surfaces exposed to operating or maintenance personnel. The applicator typically comprise an applicator body and valve module formed from metals, such as aluminum, having high thermal conductivity. Various measures are taken to insulate the dispensing equipment from nearby personnel or otherwise prevent undesired exposure of the hot applicator surfaces to the personnel. For example, insulating coverings such as blankets or flexible outer pads have been used to thermally isolate the applicator. This can reduce the ease with which the equipment may be serviced. Various applicators have also been proposed that include rigid plastic covers for heat insulation purposes. In addition to the potential for exposure of personnel to the heated surfaces of the applicator, heat dissipation can increase the energy requirement to heat the adhesive or other thermoplastic material in the applicator.
For reasons such as these, it would be desirable to provide a thermally insulated applicator that can better prevent exposure of heated surfaces to personnel and also retain an optimum amount of heat in the applicator to provide better control and reduce the energy used by the applicator.